618 



SCIENCE 



[N. S. Vol. XXXVIII. No. 983 



tween the two pairs of soluble and insoluble sul- 

 phates and carbonates. Naturally the greater the 

 excess of sodium carbonate the larger the propor- 

 tion of insoluble sulphate converted into insoluble 

 carbonate. In this operation it is advisable not to 

 wash at once with water, but with sodium carbon- 

 ate solution until most of the sulphates are re- 

 moved, as thereby the reconversion of the carbon- 

 ates back into insoluble sulphates is largely pre- 

 vented. In dealing with crude materials — for ex- 

 ample, the radium-containing residues from pitch- 

 blende — it is often advantageous to precede this 

 operation by a similar one, using a sodium hydrate 

 solution containing a little carbonate, which dis- 

 solves part of the lead and silica present. The 

 carbonates, washed free from sulphates, are 

 treated with pure hydrochloric acid, which dis- 

 solves the alkaline-earths, including radium. From 

 the solution the latter may be precipitated as sul- 

 phates by sulphuric acid and reconverted back 

 into carbonates as before, or sometimes more con- 

 veniently they may be precipitated directly as 

 chlorides by saturating the solution with hydrogen 

 chloride. This is a very elegant method of great 

 utility in the laboratory, for the most probable im- 

 purities, chlorides of lead, iron, calcium, etc., re- 

 main in solution and only the barium and radium 

 chloride are precipitated, practically in the pure 

 state, ready for fractionation. 



The price of radium appears for some 

 time to have been holding steady at about 

 $120 per milligram of radium metal. This 

 does not mean that the material is bought in 

 the elementary condition, but that the 

 radium chloride and radium bromide, which 

 are on the market, are paid for on the basis 

 of the metallic radium they contain. This 

 method of payment is a distinct advance 

 over the old method of paying the same 

 price indiscriminately for the chloride or 

 bromide. This price of $120 per milligram 

 of the taetal is equivalent to approximately 

 $91,000 per gram of radium chloride 

 (RaClo), or $70,000 per gram of anhydrous 

 radium bromide (RaBrj). Whether this 

 price will rise, fall or remain stationary 

 can not be predicted. There is no question 

 that there is to be an increased radium 

 production and that meso-thorium is also 

 coming upon the markets in increasing 



quantity, but the uses of and demand for 

 radium are apparently developing at an 

 even greater rate. Furthermore, the supply 

 of the material is limited and no large re- 

 sources are in sight. Only one estimate has 

 been published of the total quantity of 

 radium in the Colorado carnotite deposits, 

 and that was 900 grams. This estimate is 

 at least five times as large as has been made 

 by any employee of the Bureau of Mines, 

 reckoning all known deposits in the whole 

 American field, even including material too 

 low grade to be marketable. Besides the 

 radium, the uranium and the vanadium 

 present in carnotite are available assets, 

 and recent developments indicate that all 

 the uranium produced will soon be readily 

 sold, while it is well known that there is a 

 ready market for vanadium for vanadium 

 steel. 



The value to the public of these deposits 

 is, however, not to be measured in dollars 

 and cents. The value of the radium output 

 of America will never compare with that of 

 several of our common metals. The totai 

 value of the radium in the world's output 

 of radium ores in 1912 was little more than 

 $1,000,000. Accordingly, the value must 

 ever be reckoned in what it can accomplish 

 for the public knowledge and the public 

 weal. No certain prediction can be made 

 of the ultimate value of radium, or of its 

 possible applications to science or medicine, 

 but enough has been done to show that 

 radium is worthy of the fullest investigation 

 by our highest scientific and medical au- 

 thorities. Developments in its application 

 to medicine are coming fast. The foreign 

 medical press contains many apparently 

 authentic reports of cures by its use. Inter- 

 esting developments are also under way in 

 America, and those who have had the 

 largest personal experience in its use are 

 most enthusiastic over its future applica- 

 tion. The public may soon look to impor- 



